Differences in geography caused the Silk Road to decline and expanded the Indian Ocean trade. Both routes experienced different kinds of difficulties. The Silk Road, which included mountains, deserts, rivers and grasslands, was harder to travel due to the fact that those on it had to go either by foot or by horse. On the other hand, the Indian Ocean trade route was faster because of the use of ships. Using ships allowed this route to cover more territory, which included the Arabian, South China, and Red Sea, along with the Indian Ocean. Both routes had dangers, including bandits on the Silk Road; pirates and storms on the Indian Ocean route. Although both were harsh and dangerous in their own ways, overall, the Indian Ocean trade route was the better route.
The Bubonic Plague was spread mainly through the Silk Road creating the first ever Pandemic known to the world. The Bubonic Plague started in western Asia by the Mongolians. The Silk Road used horses to trade goods across the many regions. The animals created a home for fleas which was the main animal that spread the plague all throughout Europe and caused two - thirds of the population to die. The Bubonic Plague nevered reached the Americas and only infected Europe. This was because the east and west hemispheres were separated by the Atlantic Ocean. Therefore, the plague could only be passed on by fleas and it was not airborne, so the best way to prevent the disease from spreading was trading through the sea instead of the Silk Road. They were both able to spread the disease but the Indian Ocean Trade Route did not spread it as much as the Silk